The hotfix is now available from MS : http://support.microsoft.com/kb/2509007 

For anyone out there with a problem with stalled software updates (especially with large bundles), the following link will be very useful information for anyone experiencing this issue when software updates hang for no apparent reasons during a build via Task Sequence. A reinitialization may help but the issue appears to be random. Microsoft outlines more of the issue here, and more information will be made available from Microsoft when the root cause is found. 

Logs affected:

No progress in the following logs when issue occurs during the running of a Task Sequence:

  1. UpdatesStore.log
  2. UpdatesHandler.log
  3. UpdatesDeployment.log
  4. CAS.log
  5. SMSTS.log logs that it is repeatedly waiting for a Job Status Notification.

Summary of remedies:

1. Spilt up the Office updates from the main security update bulk. More information here.
2. Remove Intel Mass Storage Drivers from the Task Sequence and let Windows 7 install the default Microsoft drivers.

Credit to Brian Huneycutt for the entry below: